Automatic stoker.



A. co-TION. AUTOMATIC .STOKER.

APPLICATION. FiLED MAY 4 |910..

Patented Jan. 11, 1916.

TTORNE YS A. coTToN.

AUTOMATIC sToKER.

APPLICATION FILED MAY 4. 1910.

A. COTTON. AuoMATICsToKER.

` APPLICATION FILED MQY 4. 1910` l Patented Jan. 11, 19106.

l1. SHEETS-SHEET ALFRED COTTON, OF NEWARK, NEW JERSEY.

AUTOMATIC STOKER.

Specification of Letters Patent. j `Pate11tid Jan. 11, 1916.

Application filed May 4, 1910. Serial 1\To.`559,287.l

To all whom it may concern.' v

Be it known that I, ALFRED COTTON, a subject of the King of Great Britain, and

resident of the city of Newark, county of Essex, and State of' New Jersey, have invented certain new and useful Improvements in Automatic Stokers, of which the following is a specification, reference being had therein to the accompanying drawings, in whichv Figure l is a front elevation of the'stoker and a portion of the front of the furnace; Figi)J a side elevation, the furnace front being shown in vertical sectional view; Fig. 3 a central vertical sectional View substantially on the line III-III of Fig. l; Fig. l a plan view with the fuel hopper removed; F 5 a horizontal sectional View substantially on the line V-V of Fig. 1; Fig. 6 a similar view through the shovel .compartments, substantially on the line VI-VI of Fig. l; Fig. 7 a horizontal sectional view of the furnacev showing diagrammatically the throw of the fuel'by the shovels; and Fig. 8a detail vertical sectional View showing the means foroperating the fuel gates. Fig. 9 a detail sectional View of the diaphragmclutch controlling chamber. 'f

T his invention relates to improvements in that class of automatic .stokers in which small portions of fuel are successively deliveredover the fire to progressively cover the ire with fresh fuel, each successive throw of the shovel,.or fuel delivering device, depositing the fuel over a dierent por'- tion of the grate. 4 1

One of the objects of the invention is to provide such a Stoker with a horizontally-v swinging fuel delivery device whereby the fuel will be delivered in alayer of uniform thickness over the grate and the device will distribute the fuel over a grate of considerable lwidth. I have found that verticallyswinging fuelV delivering devicesA do not properly distribute fuel over grates of any considerable width.` I have also foundthat with my horizontally swinging fuel delivering device I am able to readily cover grates of extreme width and of any desired length or depth.

Another object of the invention is to pro` vide means whereby the horizontally-swinging shovels will be automatically adjusted as to the speedand strength of their movements and as to the arcthrough which they move, in order to secure an even distribution of the fuel. and to. prevent the 4fuel being 4thrown against the? side walls of the're box,

particularly when throwing the fuel the extreme deptlr of the grate.

Another object of the invention is to provide a pair of horizontally moving shovels and means to operate said shovels alternately, each 'shovel being arranged 'to deif liver fuel over one half of the grate.

A further obj ect of the invention is to provide means whereby the stoker will be automatically stopped and started by the draft apparatiis, .the purpose being to have the stoker operating when the draft is on and to stop the s tker when the draft is shut off.

Other important objects and advantages o the invention will be pointed out hereina ter..

Referring to the various parts by immerals, l designates the boiler; 2 the smoke box door which gives access to the boiler tubes; 3 the fire-,brick lining; 4 the dead plate;

5 the grate bars; 6 the fire door and 7 its y baffle plate. v

8 designates the usual furnace front which carries the stokerrmechanism and 9 and l0 are baffle plates whichaid in protecting the vfurnace front'from vthe heat of the lire.

These plates may. be provided with perforations 1l to admit of circulation of air -to keep them cool. and to admit air over the o grate to improve combustion.

The Stoker-.mechanism is carried by three face of the boiler front and prevents any forward movement of the bottom plate through the stoking aperture.

The fuel distributing shovels are carried byshovel arms lwhich are .mounted on vertical pivots 1S extending between the bottom plate andthe intermediate plate, said pivots projecting upwardly through the intermediate plate, for a purpose which will be hereinafter described.

The bottom plate is provided with up-A wardly extending walls 19 and Q0, said walls bemg arranged on arcsrstruck from the centers of the shovel pivots 18, said `concentric lOO wall of the furnace, as shown clearly in F ig. 6. The shovels swing in the curved racesthus formed and deliver the fuel over the grate -with a horizontal movement. The

centers of the shovel pivots are directly in the rear of the side walls of the stoking aperture. r1`he shovel-carrying arms 17 are secured tothe tops of the shovels and extend forwardly-over the shovel to form a Y.

guard 21 which prevents the fuel rising above the shovel during the throwing opera tion. The vcurved walls 19 extend to the intermediate plate 13 and from a close joint therewith,while the plates 20 terminate Ashort of the-middle plate to leave horizontal openings through whichAt-he shovel arms swing.' with upwardly projecting walls 22, said wallsy being parallel and extending rearwardly from the side walls of the stoking aperture and having openings 23 therein through which extend the outwardly projecting lever extensions 24 of the shovel arm.

The rear edges-of the bottom plate and the middle'plate are connected together by vertical plates 25 which are connected at their outeredges to they rear edges of the wa'll 22 andl at -their inner edges tothe rear edges of the walls 20.A The rear ends l of the shovel races are closed by gates 26 which are pivoted on bolts 27 extending horizontally across the upper portion of the races, the ends of said bolts being secured to the rear endsvof the walls 19 and t0 theA inner ends of the plates 25. These gates are provided with flanges at their lower ends `which tit over the rear edge of the bottom plate and thereby close the rear ends of the shovel races'. 4The plates 25 are secured in position by bolts 25a so that they may be` readily removed together with the gates 26 and thereby permit of the removal of the Y.

shovels.

The plates 12, 13 and 14 are connected'together by vertical bolts 28 and the top plate is bolted to the boiler front by bolts 29 which pass through outwardly extending lugs 30 formed at the upper edge of said plate, as shown clearly in Fig. 1.

' The top plate is provided at its inner corners with the depending. angular flanges or extensions 31, one member of said flange fitting closely against the furnace front, the other member thereof being parallel with the side edge of the plate. These flanges extend slightly below the bottom plate as The bottom plate is also formed memes Pivoted on a central vertical .shaft 36 mounted in suitable bearings near the rear edge of the plates 12 and 13 is a double armed horizontal lever 37. This lever extends rearwardly from the shaft 36 and con-- nected to each arm thereof is a link 3S, the other ends of said links being connected to, the adjoining spring extending lever 33, whereby said levers and the double armed lever 37 will move in unison and in the same direction. Shaft 36 extends through the intermediate plate 13 and is journaled in a bearing 39 formed on the under side of a cross bar 40 of the top plate, which will be hereinafter more fully described. Secured rigidly to the shaft 36 above plate 13 is a doublearmed lever'41, said arms normally lying parallel with the front wall of the furnace. Loosely pivoted on the shaft 36 below the lever 41 is a claw like cam 42 having the arms 43, said cam being in general shape like a pair of external calipers with its arms somewhat extended. @n the upper surface .of'said cam 'equal distances from the center line thereof are formed threaded lugs 44 in which are screwed adjustable contact rods 45, the inner ends of said rods being in such position that they may be brought into contact with the forward faces of the arms of the lever 41 as the cam 42 is rocked on its pivot. By adjusting the contact rods the time of contact between said rods and the arms 41 may be properly arranged and the amount of movement which it is desired to give the shaft 36 may be secured. Connected to the cam 42 at a point midway between its ends and at a suitable distance rradially from the center of its pivot is .an

operating pitmanl 46, the other end of said To the side members of these pitman'being connected to a Isuitablerecip-` rocating means, as will be more fully hereinafter described. It will, therefore, be seen that by vibrating the cam 42'the required amount of motion will be communicated to the shaft'36 and through the lever 37 and links 38 to the spring extending levers 33.

The pivots 1S of the shovels extend above the intermediate plate and on each of said pivots above said plate is rigidly secured a two-armed shovel latch 47, one of said arms 48 constituting a latch arm and the 4other arm 49 constitutinga setting arm. 0n the plate 13 adjacent each pivot is mounted a Lieaesa portion of the arms 43. VBetween said por-' tions 43fhis; secured a latch settmg roller 53.

The arm of the locking lever overlies the rloifurcated portion of the vcam'arins 43. On the upper surface of each arm 43 is formed a threaded lug 54 in which vis m unted an adjustable trip The trips 55 are so located that when the claw cam 42 has nearly completed' its movement in one direction the trip 55 will contact with the arms 52 of the locking lever 50 and move said lever suiciently to release-the shovel latch 47. The

described. On the plate 13 is arranged a stop 58 against Awhich the arm 56 rests after the shovel latch is released from the locking lever. By this means the locking lever is held in position to loe properly engaged by the shovel latch.

From the foregoing it will be noted that also be noted that both shovels are withdrawn at Vthe time of therelease of one shovel, that is to say, one shovel is just coinpleting its 'rearward movement when the or throwing movement. This is important as will be more fully hereinafter set forthffY ln order to progressively vary the throw of the shovels and thereby progressively cover the grate with fuel means are provided for gradually'varying the tension of the springs 35. This means, as shown in the drawing, consists of an approximately heartshaped cam 59 mounted on a vertical sha-ft GO which carries near its lower end-a worm gear (S1. said gear'being driven by af worm 62. A bar G3 provided with rollers (i4 engaging opposite sidesof the cam is connected to the adjusting lever 33. |The cam 59 is formed approximately as shown, 'y in order of the bar 63.

setting roller 53 of the outwardly movingthe shovels are operated alternately. It will other shovel isieleased to make its forwardA that there hwill be ay uniform rate of movement ot thebar 63 throughout the rotation of thel cam 5S). The bar (33 carries the perforated lug 65 which slideson the guide pin (3o to secure theproper reciprocating motion It will thus be seen that during the rotation ot' the cam 59 the levers will be swung on their pivots, one ot' said levers being moved-outwardly and in an arc bringing the end of the bolt 34 closer to the pivot 13 of the shovel and closer to the point of attachment between the inner end of the actuating spring 35 and the extension of the shovel arm. It will also be noted that the center line of the spring will be varied with respect to the longitudinal center line of the Stoker and also becoming more and more ac-utely inclinedto'ward said center line as the tension of the spring 35 is released and becoming more and more obtusely inclined and nearer a perpendicular of the center line as the tension on said springs is increased. 1t will, ot course, be understood that the release point of the shovel is approximately on a line drawn from the point of attachment between the spring and the arm 34 and the pivot of the shovel at'terfthe'shovel has completed its fuel throwing movement. It will, therefore, be seen that the re1eased position of the shovel willI be varied to correspond with the varying position of the spring extending arm It willalso be understood that the variation of the released position of the shovel will result in the variation ot'the throw of the shovel. This variation is clearly illustrated lin'Figs.- 6 and 7 of the drawings. It' will be noted that when the spring 35 is at 'its lowest tension, the released position of the shovel is such that the fuel thrown by the shovel will be distributed laterally over Ithe greatest distance. This results from the fact that the shovel will travel through its greatest arc of movement when the spring is atits lowest tension. As the tension of the Vspring is increased the arc ot' movement, or the length I. of travel, of the shovel is restricted for the reason that the line between the center of the shovel pivot and the point of attachment of the actuating spring to the spring extending leveris moving nearer to a perpendicular position with respect to the longitudinal center line of the furnace. As the tension of the spring is decreased the arc of movement,-

pass before it reaches a point direeftlyin line4 between the shovel. pivot`and the point' of attachment of said spring to said lever. It is manifest that as the spring extending lever moves outwardly the distance through which easing j 125 -50 releasing devices.

the "arm 211 must pass before it comes'to rest becomes gradually less and less. rlllhe result is that the arc of movement of the shovel grows gradi-rally less and less until the minimum is reached at the greatest extension of the "actuating spring. lt will, of course, be understood that the springconnected to one shovel is gradually extended andthat the'y other vspringiis at the samer time permittedl to gradually contract, and that' the' greatest i tension `on bne spring is reached at'the time f "i v,By reference to Fig. 7 of the drawings it ywilly be noted that when the shovels areA working `under their highestl tension the angle 'of' throw of the shovel-will,be the lowest ,qso that the lateral spread of the fuel 'will/be, 4considerably less than when the 125 shovelfiis/fworking under its lowest tension.

`frais,isf"desirable. if the are through which thefsyh/ovel `moves in its throwing movemeilyifhwere not reduced for the high tension .'movments a great deal of fuel would be lJ '130 ithrownia/gainst the side wall of the re box. l I'twill/be seen that this would be a very undesirable condition and itis to avoid .'th'isy that the are of movement is reduced as the' tension of the actuating spring is inf' 35 creased. By this means the lateral distribution of the coal is maintained uniform while the distant or forward throw of the shovel` is increased'. This is a very important feay ture in/'the operation of horizontally swing- 40 ing shovels.

The link 46 is connected to a crank disk 67 secured to the upper end of a vertical 'shaf/t'68 mounted in the bracket 69, said f `bracket being suitably bolted to the boil'cr #5 front.l The shaft 68 carries a worm gear 70 frotatcd by means of a worm 71 carried by the driving shaft 72. By this means the clawl cam 42 is oscillated for the purpose of operating the shovel setting and shovel y The driving shaft is formed with Ia cone pulley 73 which runs loosely on thr1 shaft and is formed with a clutch memf er 74:. Slidable on the shaft and rotating therewith is a clutch member 5 7 5 operated by means of the pivoted lever 76. This lever .is provided with ap'perforated lug 77 to receive a pin 78 to lock the clutch out of engagement and the apparatus out 'of operation. The lever 76 is provided with a dog 7 9 which isadapted tolie'close to the periphery of the cam disk 67 when the clutch members are in engagement. The crank disk' isy provided' with diametrically opposite notches 80, said notches being so formed that they will be in a position to reare gIt will alsobe understood that theceive the dog 79 when both shovels are retracted or in their rearward positions, as previously described. By this means it will be impossible to stop the stoker by releasing vthe clutch when either of the shovels is in its forward position and therefore vexposed to the fire. To provide means for automatically stopping the Stoker in response to the draft the clutch lever is extended as at 8l 'and is provided with a plunger head 82. This headis engaged to bear on a diaphragm 83 forming one wall of a pressure chamber 84. This lchamber` is connected by a pipe 85 with thesteam supply pipe 86 leading to the ash pit blower or other suitable draft apparatus. spring 87 is provided vto keep the plunger against the diaphragm and to hold the two members of the clutch disengaged. 'it will, be readily understood that when the blower is in operation the pressure in chamber 84 will be such as to hold the clutch members in engagement; and that when the pressure in the chamber 84 is -reduced by reason of `shutting down the draft the spring 87 will force the plunger inwardly against the diaphragm and release the clutch members, 'thereby stopping the stoker apparatus.. On the lower end of shaft 68 is a beveled gear 88 which meshes with a similar gear 89 on' shaft 90, said shaft 90 carrying worm 62 by means of which shaft 60 is operated. rlhe top plate 111l is formed with a fuel receiving opening 91 near its inner edge, said opening being formed by a slightly raised face on which rests the lower edge of the fuel hopper 492. The rear side of the fuel hopper is supported by the cross bar 40. On'the shaft 86 is mounted the fuel feeding ram 93, said ram resting on the upper surface ofthe bottom 94: of the fuel chamber, said bottom being formed integral with the upper plate 14 and being spaced intermediate thetop plate and the middle plate 18. As the shaft 36 is oscillated the ram feeds fuel first to one shovel and then to the other, as will be more fully hereinafter described. The ram is semi-circular in plan view, its forward edge being parallel with the boiler front. Forward of the ram the fuel chamber is divided centrally by a vertical partition 95 and each pocket or portion ofthe fuel chamber is formedwith the forwardly and downwardly inclined portion 96 which leads to an opening 97 in the intermediate plate 13, said opening being just forward of the rearward position of the shovel, whereby the fuelfed by the ram will fall through the opening 97 directly in front of the shovel when the shovel is in position to be released for its forward throwing movement.

- To prevent the fuel fallingbehind the shovel, and to hold it in the fuel chamber until the shovel has reached its rearward position, timing gates 98 are pivoted onsupports 99 mounted in the fuel chamber for- 'wardly extending finger 104. which strengthening rib 102 of the top plate and on the outer end of this rod is .secured a depending finger 103. On the end ofyeach of the arms 43 of the claw cam 42 is an upv is adapted to engage the finger-D103 when the arm -13 has very nearly reached the limit of itsnrearward movement and the shovel positioned by said arm has reachedv its rearwardlatched position. lVhen the finger y10S-is moved rearwardly7 the timing gate will be swung forwardly permitting the charge of fuel to drop through ,the openingin plate 13 in front of the shovel in the shovel race. As soon as the fingers 103 and 104: are disengaged the spring pressed rod will return the timing gate to its normal closed position. The fuel hopper is provided on its rearward side with pivot lugs 105 which correspond with similar lugs' on the top plate 14 and to which they are pivoted. Said hopper is also provided-'on its forward side with similar pivot lugsl which are adapted to be connected to lugs on a latch plate 106, said latch plate being adapted to fit-within the opening 107 of the top plate and to form a ments, said means also progressively varycover for the fuel chamber forward of the fuel hopper.' Thelatch plate is provided at its rear edge with a latch 108 which is adapted to engage under the cross-bar 40 and to hold the 'hopper in placeuntil the latchplate is raised.

The front wall of the fuelchamber is provided with a door 109 through which access may be had to the interior of the ram compartment.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is l 1. An automatic stokerrcomprisinga horizontally swinging shovel, a tension means for moving said shovel throughits fuelthrowing movement, and means for varying the tension on the shovel "for successive throws to vary the-velocitv of-the shovel movement andthe longitudinal distribution of the fuel, said means also varying the inner limit of the shovel movement to vary the lateral or si dewise distribution of the fuel.

2. An automatic stoker comprising a horizontally swinging shovel, a tension ,means for moving said shovel through its fuelfor moving said shovel through its fuelthrowing movement, and means for automatically varying the tension on the shovel for successive throws to varv the velocity of the shovel movement and the longitudinal distribution of the fuel, said means also varying the inner limit of the shovel movement to vary the lateral or sidewise distribution of the fuel.

l. Anautomatic Stoker comprising a-.horizout-ally swinging shovel, a tension means for moving said shovel through its fuelthrowing movement, means for withdrawing the said shovel to the same point for each movement, and means for varying the inner limit of travelof the shovel to vary the lateral distribution of the fuel. r

5. An automatic stoker comprising a horizontally swinging shovel, a tension means for moving said shovel through itsl fuelthrowing movement, means for withdrawing said shovel' to thesame point foreach movement, means for varying the tension on the shovel for each movement, said means also varying the inner limit of the travel of the shovel in each successive movement to vary the lateral andlongitudinal distribution of the fuel.

6. An automatic stoker comprising a horizontally swinging-- shovel, a tension means for sai-d shovel, means for automatically and progressively varyingsaid ltension means for successive shovel move-p ing the released or stopping position of said shovel and thereby varying the length of travel of the shovelin successive fuel-throw-t ing movements, means for withdrawing the y shovel to the same rearward position for each vof the travel of the shovel. in its fuel-throwing movement, said tension varying means operating to increasethe tension while re- `vdu/cing the travel of the shovel and reducing throwing movement. and means forv varying?- the inner limit of the shovel"movemnt to vary the extent of the lateral-distr'bution of the fuel. i f l 3. An automatic stolzer comprisin/ghorizontally. swinging shovel, a'yt/ensionv means fr'the tension when increasing the travel of the shovel.

soA

8. Anautomatic stoker comprising a' movable shovel, 'a tension means to move said shovel through its fuel-throwing mov- Yinent, means for automatically varyingfsaid tension means for successive shovel movements, said means also varying the inner limit of thetravel of the shovel in its fuelthrowing movement, said tension varying means operating to increase the tension while reducing the travel of the shovel and reducing the tension when increasing the travel of the shovel fnd means for withdrawing tlie shovel .5to the saine rearward position for each movement.

nto. vary the inner/limit of tleslivel move- --inent, thereby varying the distance through which the-shovel travelsin successive fuel throwing movements.

10. An automatic stoker ,comprising a horizontally swinging shovel carrying an arm, a coil spring connected to said arm and serving to swing the shovel through its fuel throwing movements,`means forfwithdrawing the shovel in vopposition to said spring, means for automatically increasing the tension of the spring and for swinging it so as to change its radial position with respect to the shovel pivot, whereby the distance throughv4 which the shovel will be lmoved and the inner limit of the shovel and thereby varying the distance through which each shovel travels during its fuelthrowing movement.

12. An automatic stoker comprising a pair -of horizontally swinging shovels extending toward each other and each being arranged to deliver fuel to one half of the furnace grate, a coil spring connected to each of said shovels and arranged radially with respect to the shovel pivot, means for automatically and progressively varying the tension -of said spring on said shovel andvarying its radial position with respect to the pivot Yof the shovel, means Y for movingV the shovel rearwardly in opposition to theVA spring, and means for releasing the shovel to permit the spring to move it through its fuel throwing movement, whereby the strength of successive shovel movements and the inner limit of the shovel movement will be varied.

13, An automatic stoker comprising a pair of horizontally swinging shovels, curved shovel races for said shovels, radial arms connected to said shovels at their pivots,

Y, Ycoil springs connected to said arms, spring extending levers connected to said springs andA means for automatically swinging Said levers in opposite directions, whereby one shovel spring will be extended while the other one is being distended whereby the tension of one of said springs will be increased and the other decreased during successive shovel movements.

14. lAn automatic stoker comprising a pair of horizontally swinging shovels, curved shovel races for said shovels, radial arms connectedto said shovels at their pivots, coil springs connectedvto said arms, spring extending levers connected to said springs, means for automatically swinging said levers in opposite directions, whereby one shovel spring will be extended while the other one is beingdistended whereby the tension of one of said springs will be increased and the other decreased during successive shovel movements, and the radial positions of the springs with respect to the shovel pivots will be varied for eachrsuccessive shovel movement to thereby vary the distance through which the shovel travels during each throw.

15. An automatic stoker comprising a pair of horizontally swinging shovels, an arm connected to each shovel at the pivot thereof, a coil spring connected to each of said arm and radially arranged with respect to the shovel pivot,vl a spring extendingl lever connected to each 'of said springs, means connecting said" levers together whereby they will move in`unison.and means, for automatically ioving said levers a uniformdistancefor each fuel lthrowing movement, the parts being so arranged that the tension of one spring will be increased and the tension of the other decreaised during a series of shovel movementsand the radial position of each spring with respect to the attached shovel will be uniformly varied throughout the variations in the spring tension.

16. An automatic Stoker comprising a pair of horizontally swinging shovels, an arm connected to-each shovel `at the pivot there-v of, a coil spring connected to each of said arms and radially arranged ,withviespect to the shovel pivot, a spring extending lever connected to each of saidspri'ngs, means connecting said levers together whereby they will move in unison. and means for automatically moving said levers a uniform distance for each fuel throwing movement whereby the tension of one spring will lbe VVincreased and the ytension of the other decreased during a series of shovel movements and the radial position of each spring with respect to the attached shovel will be uniformly varied throughout 'the variations lin the Ispring tension, means for` withdrawing one shovel in opposition to its tension meansward position, means carried by the shovel' actuating cam to release the shovel 'locking means,- means for operating the shovel Vactuating caiii whereby said cam will alternately .set and release the shovels.

1S. An automatic Stoker comprising a pair of horizontally swinging shovels pivoted near opposite sides of the stoking aperture, a spring connected to each of said shovels and arranged to move' the shovelthrough its fuel throwing movement, a spring eX- tending lever connected to each of said springs, means connecting said leversY together, means for moving said levers to alternately increase the tension of one spring and decrease the tension of the other spring, a rocking shovel actuating cam mounted between tlie shovels, means for rocking said cam, means carried by said cam toalterf nately withdraw the shovels against the spring tension, and means carried by said cam to alternately release the shovels.

19, An automatic Stoker comprisinga pair of horizontally swinging shovels pivoted near opposite ends of the stoking aperture, a tension spring connected to each of said shovels and extending radially with respect to the pivot thereof, a spring extending lever connected to each of. said springs, means for swinging said levers to alternately increase and decrease the tension of said springs and to change their radial relation to the shovel pivots whereby the released position of the shovels will be varied and the tension of thev springs onthe shovels will be varied in succeedingl movements, y a rocking shovell actuating cam mounted between the shovels, means for rocking said cam, means carried by said cam to alternately withdraw the shovels, and means carried bv said cam for alternately releasing theshovels.

20. 'An automatic Stoker comprising a-pair of horizontally swinging shovelsmounted near opposite sides of ltheshovel stoking aperture and extending toward each other in the same horizontal plane, curved shovel races for receiving said shovels, means foi" alternately withdrawing and releasing said shovels, means for alternately delivering fuel in front of the withdrawing shovel, and a tension means for moving the shovel through its -fuel throwing movement when said shovel :is released.

2l. An automatic stoker comprising apair of horizontally swinging shovels arranged in the same horizontal plane and extending toward each other from their pivots, a curved race for each of said shovels, a tenT sion means for each of sai'd'shovels, means for alternately withdrawingv each shovel against its tension means, means for locking the shovel in its withdrawnposition., means for delivering coal in front of each locked shovel, and means for. alternately releasing the shovels to permit them to move forward under the influence of the tension means.

- 22. An automatic Stoker comprising a pair.'

of horizontally swinging qshovels extending toward each other from their points of support, a tension means connected to each 4shovel to move said shovel through its fuel -throwing movement, alocking ca-m connect-r ed to the pivot of each shovel, a'pivoted latching lever, means for alternately moving the shovel locking cams to swing the shovel rearwardly and to cause the locking cam to engage the latcliing lever, and vmeans for alternately releasing the latcliing lever to permit the released shovel to. be moved by its tension means.

23. An automatic Stoker comprising a pair of horizontally swinging shovels, a tension means for each of said shovels, a horizontally rocking shovel actuating cam mounted between said shovels, means connected to each of the shovels and adapted to' be engaged by the shovel actuating cam to swingy the shovels rearwardly, means for latching each shovel and means carried by the shovel actuating cam to release the latch devices.

24. An automatic Stoker comprisinga pair of horizontally swinging shovels, a tension means for each of said shovels, a horizontally rocking shovel actuating cam mounted between said shovels, means connected to each of the shovels and adapted to be engagedby the shovel actuating cam to swing,A

the shovels rearwardly, means for latching each shovel, means carried by thevshovel actuating cam to release the latch devices, and means for automatically varying the tension means whereby successive throws of the shovels will be varied.

25; An automatic stokei` comprising apair of horizontally swinging shovels, a tension means for each ofv said shovels, means for alternately setting 'and releasing said shovels and for ,alternately increasing the tension of one of the shovel tension means and decreasing the tension of the other shovel tension means.

2G. An automatic stoker comprising a horizontally swinging shovel, a tension meansV for said shovel, and means for automatically 4varying the tension of the shovel tension means and varying the in-y lli et saen", autom ner li it Iof the arc of travel of the shovel.

v,/28'. .An automatici 'Stoker comprising a pair y/of horizontally swinging shovels, a shovel actuating cam mounted between said shovels, means for rocking said cam, means 'operated by said cam for alternately setting and rreleasing each of the shovels, a ram compartment above the shovels, a horizontal rotar-y oscillating ram in` said ramy compartment', andmeans wherebythe shovel actuat- 2 in y('iain will actuate the ram. ,o s

2.9.; An automatic stoker comprising a p ir vof horizontally swinging shovels exending toward each other, an actuating spring yconnected/ to each y,of said shovels, vspring extending levers connected to said springs,'a tical'ram shaft located between the shovels and in the rear thereof,

a lever loos/ely mounted on said shaft, links I connectingy said?? lever to the spring extending levers, tv/shovel actuating cam, means for rocking"said/y cam, means operated Aby 4said to alternately set and release the `shovels,means'carried by said cam adapted Y je torockfthe/ram shaft, a ram compartmenu' 35 'and horizontal ram in said compartment and rirgidly'connected to the ram shaft.

Y30. An'automatic stoker -comprising a horizontallyswinging shovel, a` shovel actufatingcann meansoperated by saidcam to i4o"self/and,release the shovel, a tension means shovel :to movevit throughits fuel thr'wing movement, a fuel feeding ram, a fuel `gate between the ram and the shovel, and'"meansoperated by the shovel. actuating l5 fc/am" toA withdraw the gate to permit fuel to ,passy to the shovel when the shovel has Areached itsv rearward position. "31.An automatic Stoker comprising a horizontally swinging shovel formed with a 'verticall fuelengalging plate and with a forwardly\l projecting ovcrhanging -part alongfthey :upper edge of the vertical fuel :engaging pilatefand means for operating saidshoveli" l it/ic stoker comprising a f Upairgof l:shovel 'fa' tension means for said veis, yaf'fsh actuating cam for alterand releasing said shovels, a aft, a lrotary oscillating ram y'ed fuel alternately to the er on the ram shaft, and means y *e* shovel actuating cam to en- I tento oscillate the ram. tornati@ stoker comprising a shovels, a', tension means for said shovels, a shovel actuating cam for alternately set-ting and releasing said shovels, a vertical ram shaft, a rotary oscillating ramadapted to feed fuel alternately to rthe shovels, a two-armed lever on the ram shaft,

and means carried by the shovel actuating cam to alternately engage the arms of said lever to oscillate the ram to correspond with the oscillations of the actuating cam. y

34. -An automatic stoker comprising a pair ofhorizontally swinging shovels, a tension means for moving said shovels through their fuel throwing movements, a shovel actuating cam pivoted between said shovels and provided with two arms, means carried so by each of said arms for alternately setting and releasing ythe shovels, a horizontally oscillating arm, fuel gates controlling the passage of fuel from the ram compartment to the shovel compartment, mea-ns adaptedl i to be engaged by the arms of the' shovel actuating cam to raise the gate that controls the fuel supply for the shovel which is in its rearward position.

35. An automatic stoker comprising a pair of horizontal shovels, a tension'means for each shovel, means for alternately moving the shovels rearwardly againstthetension device, means for releasing one-shovel for its fuel throwing movement when the other shovel is in its vrearward position, and means to permit the stopping of the operating mechanism only when both shovels are in their rearward positions.

36. An automatic stoker comprising a 100 pair of horizontal shovels, a tension means for each shovel, means for alternately movl ing the shovels rearwardly against the tension device, means for releasing one shovel for its fuel throwing movement when the other shovel is in its rearward position,` and means to prevent the stopping of the operating mechanism when either shovel is in its forward position.

37. An automatic stoker vcomprising a shovel, an operating mechanism for said shovel, a drive shaft, means connecting the drive shaft to the operating mechanism, a drive member loosely mounted on said shaft,

a clutch for connecting said driving member ,in driving relation with said shaft, a locking rdisk operating with the driving mechanism,

and means whereby said disk will prevent the disconnection of the clutch when the shovel is in itsgforward movement. 12o

88. An automatic stoker comprising a shovel, an operating mechanism for said shovel, a drive shaft, means connectingthe the shovel is in its forward movement, and means whereby the locking disk will permit the clutch to be disconnected only when the shovel is in its rearward position.

39. An automatic `stoker comprisingv a swinging shovel, a tension meansfor said shovel, means for automatically increasing the tension' of said tensionmeans for successive shovel movements, and reducing the length of travel of the shovel as the tension pair of horizontally swinging shovels, means for alternately moving said shovelsfrearwardly, means'for locking them in their rearward position, means for releasing the shovel locking means for 'one' shovel as the other shovel is brought to its rearward locked position, a horizontal oscillating ram for feeding fuel'alternately to the shovels, means actuated by the means for moving the shovel to its rearward position for oscillating the ram, and means for moving the shovels through their fuel-throwing movements when the shovel locking means is released.

4.1.'An automatic stoker comprising a plurality lof horizontally movable shovels, means for successively operating shovels, a4 fuel feeding means and means forl varying the inner limit of successive throws of each shovel. i

42. An automatic Stoker comprising a horizontally swinging shovel, a horizontally said oscillating fuel feeding ram, a horizontally oscillatmg shovel actuating means, said means varying the inner`limit of movement of the shovel. for each succeeding throw of said shovel. I

43. An a-utomatic stoker -comprising a horizontally swinging shovel, a horizontally oscillating fuel feeding ram, a horizontally oscillating` shovel J actuating means, and

meansv for varying the inner limit of successive throws ofthe shovel.

4l. An .automatic stoker comprising a horizontally swinging shovel, a fuel feeding means, a horizontally oscillating shovel actuating' means, means for varying the speed of the shovel in its fuel throwing movements and for varying the inner limit of the lshovel movements.

45. An automatic Stoker comprising a horizontally swinging shovel, a fuel lfeeding means, a horizontally oscillatingsshovel actuating means, means for varying thefspeedof the shovel in its fuel throwing movementsa and` for varying the inner limit of the shove-l-\.V`VV

movements, the speed of the shovel increasing as the length'of movement decreases, the speed of the shovel being decreased as the vlength of the shovel` movement is increased.

In testimony whereof I hereunto Vaffix my signature. in the presence of two witl nesses this 9th day of September, 1909.

ALFRED COTTON. 

